Grandchildren
Queen Victoria arranged the marriage of her eldest son and heir-apparent, the future Edward VII of the United Kingdom to Alexandra of Denmark, the eldest daughter of King Christian IX, which took place on March 10, 1863. Among their six children were George V of the United Kingdom (who was also Emperor of India throughout his reign) and his sister Maud of Wales (who would later marry their cousin King Haakon VII of Norway, another grandchild of Christian IX, on July 22, 1896). However, these two marriages were not the only unions amongst and between descendants of Victoria and Christian IX.
The second son of Christian IX, Prince William, became King of Greece as George I shortly after his sister Alexandra's marriage due to this new connection with the British Royal Family. On October 27, 1889, his son, later Constantine I of Greece married Sophia of Prussia, a granddaughter of Victoria, forging another union between descendants of the British queen and the Danish king.
Dagmar of Denmark, one of Christian IX's daughters, married Tsar Alexander III of Russia and became empress-consort as Maria Feodorovna. Her son, Nicholas II of Russia, married Alix of Hesse and by Rhine, yet another granddaughter of Queen Victoria of the United Kingdom, on November 26, 1894, and she became empress-consort as Alexandra Feodorovna.
Other grandchildren became monarchs in their own right or consorts. Christian X of Denmark was the elder brother of Haakon VII of Norway and thus another grandson of Christian IX of Denmark. William II, German Emperor was the elder brother of Sophia of Prussia and thus another reigning grandson of Victoria. Lastly, Victoria had two more granddaughters who became queens: Marie of Edinburgh, who married Ferdinand I of Romania, and Victoria Eugenie of Battenberg who married Alfonso XIII of Spain.
Christian IX was therefore the grandfather of an emperor and two kings who all married granddaughters of Victoria, one of whom (Maud of Wales) was also a granddaughter of Christian IX. In total, five of his grandsons were reigning sovereigns.
Victoria, meanwhile, was the grandmother of an emperor, a king-emperor, four queens consort and an empress consort.
Read more about this topic: Royal Descendants Of Queen Victoria And King Christian IX